Releasing clamp



K. A. HAwLEY RELEASING CLAMP Oef. 10, 1933.

Filed July V51 195o Vmake them so strong as to pull it over.

Patented Got. lil, 1933 rrss RELEASING CLAMP Kent A. Hawley, Baltimore, Md., assigner to Locke Insulator llorporation,"Baltimore, Md., a corporation ci Maryland y Application .lilly 3l, 1330. Serial No. 472,036

i9 Claims. (Cl. 24844-31) The invention relates to clamps employed for suspensing conductors such as are used in high tension transmission. lines.

It is well known that it is customary to suspend conductors by means oi clamps carried by strings of insulators hung from towers which are frequently located long distances apart. .lt frequently occurs that sleet or ice may accumulate upon the conductor at one side of a towerl Y Vaclamp which may, by removing a few parts,

and not at the other side owing to the.' existence of local storms and the difference in atmospheric conditions along the line. Further' more, particularly where the line passes over the mountains or valleys, high the binging oi a'greater pressure upon the conductor at one side oi a tower. Regardless of which may be the case, the fact that the strain is unedually distributed as that portion of the conductor or sleet or that portion which is subjected to the action of high. winds exerts a greater strain at one side of the tower than at the other. This is highly objectionable and it has occurred that towers have been ypulled over. It is, oi course, desirable to build the towers as light as possible to withstand the service ior which they are intended and it is not practical to to be capable of withstanding every conceivable strain.

With the above facts in View I have devised the present invention which has for its lgeneral object Y the provision of a` suspension clamp adapted to open and release the conductor upon the occurrence o an excessive strain at one side. or the other of a may slide through until the strain is equalized, thus relieving the tower of those forces tending An important object o vide a clamp for this purpose which is capable oi maintaining its grip until the string oi' insulators from which it is suspended hasr been pulled through an arc of a certain predetermined extent or moved into a certain angular position with respect to the normal or vertical, release occur 'ing only inclination has been passed.

Another object of the invention is to provide a clamp embodying cam means for holding it in gripping relation to the conductor, the conductor' itself supplying theforce for effecting' re` lease when the cam means becomes ineffective.

A further object of the invention is to pro-- vvide a clamp having suspension means located at the longitudinal axis ot the conductor so clamp which will manufacture, easy to assemble and install, posiwinds may cause which is coated with ice tower so that the conductor` the invention is to pro- Yforcing bead 13 which merges after the safe angle or that the clamp may accommodate itself to vibrations of .the-conductor withoutexerting any bending strains thereon.

. Yet another object ofthe invention is to provide a clamp of this character incorporating spring means for maintaining a tight vgrip upon the conductor and compensating for any manufacturing variations in the parts. i

Another object of the invention isto provide be converted into the ncn-releasable type, ifV desired. w Y v c An additional object is to provide a releasing be simple and'inexpensive to tive in action, efficient and durable inservice, land a general improvement in the/art.

VTo the attainmentof the kforegoing' and other objects and advantages, the invention-preferably consists in the details of. constructiorrand the arrangement .and combination/of. partscto be hereinafter more fully described and' claimed, and illustrated in the'accompanying drawing in which:

AFigure 1 is a side elevation of a clamp constructed in accordance with my invention, andA Figure 2 is a vertical cross section taken on the line`2-2 of Figure 1.

Referring more particularly to the drawing, I have shown thel device as comprising a main or lower clamping member 10 preferably formed as a casting and having alongitudinally extending cable seat 11 whiching member has preferably flaring orbell ends 2 so as to avoid Contact of the edges thereof with theconductor and thereby eliminate the bringing of any bending vstrains upon the conductor in case of vibration or dancing of the conductor as is bound to occur in service. It may be more or less an immaterial'detail but the edges of this clamping closed as having a somewhat thickened reininto a transverse rib 14 located at the center. Furthermore this lower` clamping member is shown as provided at is curved in cross sec- `tion to nt the cable and which is also longitudimember are here disopposite sides of itsAcenter with lateral trunmons 15 preferably having ing outer ends 16 for a purpose to bedescribed.r

-At each side and spaced from its center this downwardly eXtendclamping member is also providedwith apertured ears 1'?. i

The conductor 18 of course lies within this lower clampingv member in engagement with with apertured ears 21 above and spaced from' the ears 17 and provided for the purpose of receiving the legs of U-bolts 22 which also pass through the ears 17 and which carry spring washers 23 and nuts 24. At its center the top surface of the upper clamping member 19 is preferably grooved, channeled or recessed as shown at 25.

In conjunction with theclamp I provide 'suspension means here disclosed as comprising a pair of links or arms 26 having their lowerends apertured at 27 for engagement upon the Vtrunnions 15, the heads 16 ofthe latter preventing accidental disengagement after assembly has once `been effected. Passing through the upper ends of these'links is a bolt 28 carrying a nut V29, this bolt also passing through and pivotally connecting the links with a clapper-pan or socket member 30 of the type adapted to be engaged, for'instanoeupon the headed pin of a supportclamp.

The clamp further comprises pairs of presser ing insulator or `the like, not shown, above the levers' 31 of a resilientl character havingdownward projections 32 at'theirouter ends engaging vided at their within which thevbight" portions of the U-bolts 22 are seated. These levers 31 are arranged in i overlapping and staggered relation and their inner ends are pivotally connected as by a pin 34, cottered at 35,'with" a i which is-provided at its `lower end with an exlarms Vwhich are joined` toward This is,however, a mere matter of: terminology'. `rand is of no consequence.

' When `the -clamp islassembled andy engaged upon the conductor, it is of course :apparent that the'member l() isvb'eneaththe conductor, Ithe 'member 19 thereabovewhile'the U-bolts 22 straddle it.l Aslong as the fork 36 is in itsY nor- 'mal or"upriglit"fposition, as'shown inthe draw- '7ing, the extension 37 reacting against the bottom ofthe groove or recess 25'will cause the ends 32 to press downwardly on the top of the end portions of the upper-clamping member.

` gree of pressureland it is for this 'reason that means-the gripping pressure the seat 20 is' occur at the center or" the upper 20 will probably be, at least to all intents and purposes, straight. The clamp is tightened upon the conductor by drawing up onV the nuts 24 on thel U-bolts and it is apparent that by this oi" the clamp upon the conductor may be made as strong as def'sired. -Under lnormal circumstances the suspension elements 30,and 26 as well as the 'fork 36 will remain in vertical position and there will tops with retaining grooves 33- fork 36 which has its upper endl straddlingi and spaced from the bolt 28-and the groove or recess l' 25. `Instead of `stating that there are actually' preferably upwardly bowed, this Vbowing `compensating for any downwarddeiiec- 'tion which may 'clamping member so that under strain the seat "position considerably inclined withV respect to the normal or vertical position. When this occurs, it is clear that the bolt 28 will strike against one side or the other of the fork 36. As the angularity `increases a certain critical point is reached where 'the extension 37, which really constitutes a cam, will ride off from or out of the recess or groove 25. There is then no reaction against the pin 34 and the inner ends of the presser levers 31, together with the pin 34, may drop down until they engage against the top of the central portion of the upper clamping member 19. There is consequently nothing exerting an upward strain yagainst the bight-portions of the U-bolts 22 and their holding .action is therefore-suddenly reduced, relievingthepressure of-the upper clamping member 19 the conductor and permitting, the conductor to slip through the clampruntil the strain on the conductor at both sides of the clamp is equalized. The actual downward-movement of the inner ends of the presser levers 31 under these conditions may be as little as one-sixteenth of an inch but I have discovered that this is ample Vto permitthe cable to slip through and-equalize the strains. The exact distance is oi course immaterial and depends obviously onthe pro` portion of the parts, the location of the pivot iulorum points, etc. v Y

inv case i'r is so desired, the clamp may be used without the releasing feature in which event the forli 36 and presser levers 31 are omitted tc-- gether with their connecting pin 34. vShorter U-bolts can then bey used or ifthose shown at 22 have their legs threadeda suiiicientdistance, the nuts 24 may simply be turned up so as te eiiect thev clamping action on the cable, the bight portions oi the J-bolts then bearingupon the upperclamping member 19 instead of upon the levers. It is thought thispossibleemployment will be obvious.

From the foregoing vdescription and a study of the drawing it will be apparent that I 'have thus provided-a simply constructed, inexpensive and `easily installed clamp and one which will be Vcapable of performing all then functions for which it is intended. It is believed that the construction,` operation and advantages willv be readily apparent to one skilled in the art without further explanation.

While I have shown and described the preferred embodiment of the'invention, it should be understood that the disclosure is merely an exempliication of the principles involved as the right is V"reserved to `marke all such changes in the details ofA construction as will widen the field of utility and increase the adaptability of the device provided such changes constitute no departure from the spirit of the invention or the scope oi the claims hereunto appended.

Having thus described the invention, I claim:

1. AA suspension clamp comprising a pair of clamping members engageable upon opposite sides of a conductor, bolt means urging said clamping members toward each other, suspension means, and pivoted trip operated for rendering said bolt means ineffective upon swinging ofi,l said suspensionmeans beyond av l clamping' member 'predetermined limit;

2. A releasing "clamp comprisingA aV lower' adapted tosupport a conduce tor', an upper clamping member, suspension- [means pivotally connected ywith'the lower clamp# ing member, bolt means urgmgsaid clamping members toward each other, and pivoted means operating upon lateralswingmg `of the suspensionfmeans beyond 'a predetermined extent'to render said bolt meansV ineiective.

3. A releasing clamp comprising a lower y clamping member adapted tov support a conducsuspension clamp v clamping member,

tor, an upper l connected with the lower means pivotally Vving member, bolt means urging saidv clamping named means being members toward each other, operating upon sion means beyond apredetermined` extent to render said bolt meansV ineilective, said last' ond clamping member, bolt means engaging both j clamping members, suspension'means connectedwith one clamping member, rigid meanscoacting with the upper clamping member and the bolt means for maintaining the clamping relation, and pivoted means operable upon 'swinging movement of the suspension means through a predetermined arc means ineffective.

5. A suspension clamp oomprising'a pair of clamping members, bolts connecting the same, suspension means pivotally connected with one clamping member, a trip member engaging the upper clamping member and reacting thereagainst, means connected withthe trip member and engaging the bolts and the upper clamping member for causing a reaction between them to maintain said clamping members in clamping engagement upon a conductor, and means operating upon swinging of the suspension means beyond a predetermined limit for releasing said trip.

, 6. A suspension clamp comprising a pair of clamping members bolts connecting said members, means pivotally connected with one clamping member, a trip bearing normally upon and reacting against one clamping member, means pivotally connectedwith the trip and reacting against the bolts and one clamping member for normallyT maintaining the clamping members in clamping relation upon the conducoperating on swinging movement tor, and means of the suspension means beyond a predetermined limit for moving said trip and rendering said presser means ineffective.

7. A suspension clamp comprising a pair of clamping members, bolts connecting the same, suspension means pivotally connected with one clamping member, trip and presser means reacting against one clamping member and the bolts, and means operating on swinging movement of the suspension means beyond a predetermined extent for rendering said trip and presser means ineiective.

8. A suspension clamp comprising a pairV of clamping members, bolts connecting the same, suspension means pivotally connected with one clamping member, trip and presser means reacting against one clamping member and the bolts, means operating on swinging movement 'of the suspension means'beyond a predetermined with one clamping' member, operated means for releasing said retaining and pivoted meansY lateral swingingY of V the suspenu for rendering said last named otally connected engageable upon a conductor, suspensionextent for 'rendering said trip and presser means ineffective, the' trip and presser means including a fork, and the suspension means includingfan element4 located Within lthe fork and adapted to engage thereagainst for moving the same.

91A suspension clamp comprising a pair' of clamping members engageablc upona conductor, retaining meansA engaging the clamping members,l suspension means pivotally connected and pivoted trip means upon' swingingmovement of the conduc v-tor beyond a predetermined limit.

v1o. A clamping device comprising a clamping member adaptedto support a conductor, a

`second clamping member, bolt means engaging both clamping members, suspensionA means connected with one clampingmember, ypivoted means coacting with the upper clamp member andthe bolt'means for maintaining the clamping relation, and pivoted means operable upon swinging ymovement of the suspension means throughrapredetermined arc for rendering said vlast named means ineffective.'

11. A clamping deviceV comprising aV clamping member adapted to support a conductor, a second clamping member, =bolt means engaging both clamping members, suspension means connected 'with one clamping member, pivoted means coacting with theA upper clamping member and the bolt means for maintaining the clamping relation, other means pivoted to said pivoted means for normally maintaining the same against movement, and means operable 'upon swinging movement of the suspension means through a predetermined arc for rendering said last named means ineffective.

12. A suspension clamp comprising a clamping memberfadapted to support a conductor, a

second clamping member, U-bolts embracing j said clamping members, suspension means pivwith one clamping member, againsty the upper clamping bight portions of said U-bolts means reacting member and the lier maintaining the clamping relation, oted means operable upon swinging movement of the suspension means beyond a predetermined limit for rendering means ineffective.

13. A suspension clamp comprising a pair of 1;;

clamping members engageableupon a conductor, U-bolts embracingly engaging said members, suspension means pivotally connected with one' clamping member, pivoted means reacting against the upper clamping member andthe bight portions oi the U-bolts, other pivoted means pivotally connected with said lrst named pivoted means for normally maintaining the clamping relation of the members upon the conductor, and means operable upon swinging pension means beyond a predetermined limit for rendering said last named means ineffective.

14. A suspension clamp for a conductor comprising a pair of clamping members, suspension means therefor, and trip engaging one clamping member at a plurality of points for normally maintaining the clamping members in clamping engagement upon the conductor and cooperating with the suspension means for releasing the clamping` action upon movement of the suspension means beyond a predetermined extent.

15.' Av conductor suspension clamp comprising clamping members, a plurality of levers normally maintaining the clamping members in movement of the susi operated lever means .l

said last named holding the *levery ineffective: v posi-tion; and

means cooperating With the suspension `v.means for moving said holding means out o f iengagement with Y the. levers Yuponi movement of YK the vsuspension means `beyond a predetermined eX- tent.

16. A cenductonsuspensionv clampcomprising clamping members ngageable upon lever means reacting against oneplampingmember at a plurality of spaced points for normally maintaining a clamping action uponthe conductor, swingable means normally maintaining said levermeans eiectivasuspension means, f l

and meansl cooperating withV the `suspelfLSon means upon movement thereof beyond-a predetermined extent for swinging and-renderingsaid.

vn aaintaining means-ineiective. 1'7 A -eonductor suspension ,clamp comprising Va pair, of clamping membersengageable upon a Conductor, means reacting-againstone clamp- -ing member at. opposite sides of thecenter thereof fon normally maintaining the clamping mem?,

bers in clampingAengagementnpon the conductor, meansL normally maintaining said means a conductor,

- leversnstationaryt s movement clamping relation,A Suspensionfmeans, means fon eiective,.vsuspensionmsans and mgansnnelable upon abnormal movement; of the spension means for releasing sailinaintaining means.

{compris- ,zing a .pair of .clamping membersgf U-looltscan y the, nher! leversengaged Withinithebight portions o f, the

ried, by one :member and stradclling Ufbolts and reacting against the adjaent `elgnnpirig. member, Ameans normally holding said Suspensolmeans .and meanf.

operable upon rncwementV ot the s|. 1sp ens ion` means beyond a predetermined egtentfqr releasing said holding means.

19. A conductor suspension clamp eeinprising aj pair of clamping members engageable'npqn ad' 90 conductor, levers Y located above themelamping membersand reacting downwardly 'tliereon, 

